Protective shield for incandescent lamps



June 1 6, 1931. Q WHITMAN 1,809,878 I PROTECTIVE SHIELD FOR INCANDESCENT LAMPS Filed July 17. 1929 dttozmq Patented June 16, 1931 uairiso sTAT Es r ra r *oFFicE CHANNING WHITMAN, or BUFFALO," NEW yon-xnssronoltTorLnxIiUME con-1 01m- TION, or rouawanna, New YORK, Acouronn'rrou or NEW YORK PROTECTI E smnnn ronjnvoannnsonlwrnms Application filed July 17, 1e29.-ser1a1 no. 378,908.

This invention relates to a protective cap or shield for incandescent lamps such as are employed in the illumination of signs characterized by a hollow casing having translucent display portions in its walls.

A substantial item of thecost ofmaintaining such signs is the-expense of the replacement of broken lamps. Thisbreakage is for the most part due to the dripping or spatter ing of cold water upon the highly heated surfaces of the lamp bulbs, it being understood that in driving rain storms orcshowers or in the thawing of accumulated snow the water passes in some degree into thecasing through the numerous interstices incident to its construction. a

Modern practice requires for the illumination of signs of the kind described nitrogen or other suitable gas filled electriclamps. In

any arrangement of such lamps between a horizontal and an upright position there is at the uppermost part of the bulb a small area which becomes highly heated, much more so than the rest of the area of the bulb. It is this excessively heated portion'of the lamp bulb which is particularly exposed to spattering or dripping rain water or snow and which becomes cracked as a result, the re mainder of the bulb not being heatedto such an extent as to be seriously liable'to cracking by contact with cold water.

The object of the invention isto overcome the above disadvantages by means-of a shield or cap applicable to lamps of various diame- I ters and whichmay be readily adjusted upon the lamp. to'a .fit, preferably a substantially conforming fit, over and close to the -upper-.

most exposed surface thereof, regardless of the angle at which the lamp'may be mounted, and which by virtue of itsformand arrangement relatively to the lamp does not substantially impair the illuminating efiiciency of the lamp. a

The invention is illustrated in the accompanying drawings in which 7 *igure 1 is a top plan view of the shield applied to a horizontally positioned lamp. Figure 2 is a side elevation of the same. Fi *ure 3 is a side elevation of the shield applied to a vertically positioned lamp.

cally-withinthe sign ca-sing.

preferablyjhaving a concave surface and adapted to lie close toand covera portion of the surface of the lampbulb. 6. The cap5 is applicable to lamps of'the various sizes employed in electricsigns of the kind described, thesizes usually rangingfrom forty to one hundred watts. Said cap is of a size sufiicientto cover the portion of the bulb which becomes excessively heated during the illumination of the'lamp, thediameter of the cap being in any'case substantially less than the diameter of the major portion of the lamp bulb- The cap 5 is provided with resilient gripping fingers 7 which engage the lamp and permit universalfadjustment of the cap toposition the same upon the upper side of the lampirrespective of the 'angle at which it is mounted. The grippingfing r-s are preferably formed from wires "suitably secured to the cap. 'As illustrated, these fingers 7. constitute the ends of two wires crossed upon the top of the cap 5, the wires being secured to the capiby the passing of the ends thereof through theapertures 8 about the marginal portion of the cap and bendingthem sharply. I outwardly against theunder side of the cap to conform to the shape of the bulb. This 1 method of forming and attaching the gripping fingers tothe; cap insures a permanent connection between the two 'as' well as per-,. mitting the positioning of the eap closely.

against the lamp. The adjustable character of'the protector permits its use upon lamps positioned either'horizontally or verti- Having fully described claim:f a r 1. A, shield adapted to protect an incan descent lamp consisting of a disc having a degree of concavity such that it may be fitted substantially comformably upon said lamp my invention, I

.so as to, overlie a part of the area thereof subtended by a chord of less extent than the diameter of thelanrpflwogmirs of apertures formed in said shield an a resilient wire passing through each of said pairs of apertures and adapted to conformably engage said lamp to permit adjustment of the shield about the lamp to cover a portion of the upper exposed surface thereof regardless of the angle at which the lamp is mounted, said wires crossing at a point over said cap.

2, A shield adapted to protect an incandescent lamp consisting of a disc having a degree of concavity such that it may be fitted substantially conformably upon said lamp so as to overlie a part of the area thereof subtended by a chord of less extent than the diameter of the lamp, two pairs of apertures formed in said shield and a pair of resilient crossed U-shaped wires, the end of which pass through said apertures to conformably engage said lamp to permit adjustment of the shield about the lamp to cover a portion of the upper exposed surface thereof regardless of the angle at which the lamp is mounted.

In testimony whereof I afiix my signature.

CHANNING WHITMAN. 

